Question

I have a user control that contains a border somewhere in it. I am able to edit both the User Control Width and the Border Width from binding to two textboxes. I need to include validation when I create the binding in code so that the Border Width can’t be higher than the User Control Width.

Answer 1

I solved my problem, it was kind of easy, I thought of deleting my question better than respond to it, but maybe someone will find this useful.

class MyUserControlValidationRule : ValidationRule
{
    private MyUserControl _control;
    public MyUserControlValidationRule(MyUserControl control)
    {
        _control = control;
    }

    public override ValidationResult Validate(object value, CultureInfo cultureInfo)
    {
        int parameter = 0;
        try
        {
            if (((string)value).Length > 0)
            {
                parameter = int.Parse((String)value);
            }
        }
        catch (Exception e)
        {
            return new ValidationResult(false, "Illegal characters or " + e.Message);
        }

        if (parameter >= _control.Width)
        {
            return new ValidationResult(false, "Border width is bigger that the control width.");
        }
        return new ValidationResult(true, null);
    }
}